Characterisation of the interferon-mediated protein kinase by polyclonal antibodies
Laurent, A.G.; Krust, B.; Svab, J.; Hovanessian, A.G.
Biochemical and Biophysical Research Communications 125(1): 1-7
1984
ISSN/ISBN: 0006-291X PMID: 6210083 Document Number: 223628
Interferon-treated human cells show an enhanced level of a double-stranded (ds) RNA-dependent protein kinase activity which is manifested by the phosphorylation of an endogenous 72,000 MW protein, (p72K kinase). Murine polyclonal antibodies were used against this p72K kinase to characterize the protein kinase activity associated with immune complexes precipitated from extracts of interferon-treated cells. Precipitation of the p72K kinase by the polyclonal antibodies results in the formation of a complex in which the kinase activity is manifested by phosphorylation of the 72K protein. This phosphorylation, however, is independent of dsRNA. Such an immunoprecipitates can also phosphorylate exogenous substrates, calf thymus histones and the .alpha. subunit of protein initiation factor eIF2.